(A) Alpha diversity, as measured by Shannon index, of IPF basilar parenchymal tissue stratified by tertiles of bacterial load. IPF samples within the highest bacterial load tertile had the lowest alpha diversity. (B) Beta diversity, as measured by Bray-Curtis dissimilarity, in IPF basilar parenchymal tissue stratified by tertiles of bacterial load. Samples from the highest bacterial load tertile were taxonomically distinct from samples from the other two tertiles (C) Mean bacterial burden by qPCR endpoint fluorescence in basilar parenchyma IPF tissue stratified by clinical outcomes: by whether patients received a recent (within the preceding 90 days) antibiotic prescription, by whether patients had an AE-IPF at the time of lung explantation (transplant or death) and by whether patients died or received a lung transplant. P-values are obtained by Wilcoxon tests. *=p<0.05, ***=p<0.001, ****=p<0.0001. Abx, antibiotics; IPF, idiopathic pulmonary fibrosis; AE-IPF, acute exacerbation of IPF; MDS1, primary NMDS axis; MDS2, secondary NMDS axis; NMDS, non-metric multidimensional scaling.